php获取特定的json数组元素标记

First of all I'm sorry if this is a duplicate question but I couldn't find anything that would work and solve my problem.

I'm fetching data from a DB(Postgres) and parsing that into a Json array. The data looks like this

[{"login":"root@localhost","first_name":"Admin","last_name":"Name","title":null},{"login":"another@localhost","first_name":"More","last_name":"Data","title":"X"}]

My code to fetch this data is something like this:

foreach ($jsonData as $us) {
    $user = new App\User;
    $user->name = $us->login; //same thing for the rest of data

The error I'm getting says that I can't call data from the JSON with -> but var_dump'ing $jsonData states that it's an array with all the correct elements in it.

PS: forgot to add but I tried var_dump($jsonData['login'][0]); to get just the first login (should be "root@localhost") but it says "Undefined index: login"

Because you JSON is not store in an object, but in a array :

foreach ($jsonData as $us) {
    $user = new App\User;
    $user->name = $us['login']; //same thing for the rest of data
}